What is a primary feature of autoimmune lymphoproliferative syndrome (ALPS)?

A primary feature of autoimmune lymphoproliferative syndrome (ALPS) is indeed the increased lymphoid tissue, which can manifest as lymphadenopathy and splenomegaly due to the dysregulation of lymphocyte homeostasis. In ALPS, there is a failure in the apoptosis (programmed cell death) of lymphocytes, particularly T cells, which leads to their accumulation and the consequent enlargement of lymphoid tissues.

This condition is often associated with mutations in genes involved in apoptosis pathways, such as the Fas receptor or components of the Fas signaling pathway. As a result, affected individuals experience chronic lymphoproliferation and a range of autoimmune phenomena due to the inability to adequately regulate lymphocyte numbers and function, leading to increased risk of autoimmune disorders and malignancies.

Understanding this feature is critical in recognizing ALPS and differentiating it from other lymphoproliferative disorders, making it an important topic in immunology and clinical practice.